Simulating hydraulic fracturing processes in laboratory-scale geological media using three-dimensional TOUGH-RBSN

作     者：Daisuke Asahina Pengzhi Pan Kimikazu Tsusaka Mikio Takeda John E.Bolander 

作者机构：Geological Survey of JapanIbarakiJapan State Key Laboratory of Geomechanics and Geotechnical EngineeringInstitute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China INPEX CorporationTokyoJapan University of CaliforniaDavisUSA 

出 版 物：《Journal of Rock Mechanics and Geotechnical Engineering》 (岩石力学与岩土工程学报（英文版）)

年 卷 期：2018年第10卷第6期

页      面：1102-1111页

核心收录：

学科分类：07[理学] 

基　　金：partially supported by the National Key Research&Development Plan of China(Grant No.2017YFC0804203) International Cooperation Project of Chinese Academy of Sciences(Grant No.115242KYSB20160024) the Open Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences(Grant No.Z016003) 

主　　题：Hydraulic fracture Crack opening TOUGH Rigid-body-spring network(RBSN) Permeability Injection pressure Fluid viscosity Hydro-mechanical(HM) processes 

摘      要：In this context, recent developments in the coupled three-dimensional(3 D) hydro-mechanical(HM)simulation tool TOUGH-RBSN are presented. This tool is used to model hydraulic fracture in geological media, as observed in laboratory-scale tests. The TOUGH-RBSN simulator is based on the effective linking of two numerical methods: TOUGH2, a finite volume method for simulating mass transport within a permeable medium; and a lattice model based on the rigid-body-spring network(RBSN) concept. The method relies on a Voronoi-based discretization technique that can represent fracture development within a permeable rock matrix. The simulator provides two-way coupling of HM processes, including fluid pressure-induced fracture and fracture-assisted flow. We first present the basic capabilities of the modeling approach using two example applications, i.e. permeability evolution under compression deformation, and analyses of a static fracturing simulation. Thereafter, the model is used to simulate laboratory tests of hydraulic fracturing in granite. In most respects, the simulation results meet expectations with respect to permeability evolution and fracturing patterns. It can be seen that the evolution of injection pressure associated with the simulated fracture developments is strongly affected by fluid viscosity.